Design a class that keeps track of a student's food purchases at the campus cafeteria. A meal card is assigned to an individual student. When a meal card is first issued, the balance is set to the number of points. If the student does not specify the number of points, then the initial balance is set to 100 points. Points assigned to each food item are a whole number. A student can purchase additional points at any time during a semester. Every time food items are bought, points are deducted from the balance. If the balance becomesnegative, the purchase of food items is not allowed.